An HttpSessionState property named Session is a key and value dictionary that can store Serializable objects. The Session property is accessible through an HttpContext or a Page object. You can use the Session object to store information for an individual session, which can be a user, browser, or client application.
The session cache is easy to use, durable (storing data between IIS restarts), scalable for multiprocessor and multi-computer environments, and works with browsers and devices that don't support cookies. Adding data to the session cache is straightforward. We'll take a quick look at how to get data into the Session as well as how and why to configure different kinds of session state servers.